// @(#)root/geom:$Id: TGeoPhysicalNode.cxx 25361 2008-09-04 15:00:56Z brun $
// Author: Andrei Gheata   17/02/04

/*************************************************************************
 * Copyright (C) 1995-2000, Rene Brun and Fons Rademakers.               *
 * All rights reserved.                                                  *
 *                                                                       *
 * For the licensing terms see $ROOTSYS/LICENSE.                         *
 * For the list of contributors see $ROOTSYS/README/CREDITS.             *
 *************************************************************************/

//_____________________________________________________________________________
// TGeoPhysicalNode, TGeoPNEntry
//
// Physical nodes are the actual 'touchable' objects in the geometry, representing 
// a path of positioned volumes starting with the top node: 
//    path=/TOP/A_1/B_4/C_3 , where A, B, C represent names of volumes.
// The number of physical nodes is given by the total number of possible of 
// branches in the geometry hierarchy. In case of detector geometries and 
// specially for calorimeters this number can be of the order 1e6-1e9, therefore 
// it is impossible to create all physical nodes as objects in memory. In TGeo, 
// physical nodes are represented by the class TGeoPhysicalNode and can be created 
// on demand for alignment purposes:
//
//    TGeoPhysicalNode *pn = new TGeoPhysicalNode("path_to_object")
//
// Once created, a physical node can be misaligned, meaning that its position 
// or even shape can be changed:
//
//    pn->Align(TGeoMatrix* newmat, TGeoShape* newshape, Bool_t check=kFALSE)
//
// The knowledge of the path to the objects that need to be misaligned is 
// essential since there is no other way of identifying them. One can however 
// create 'symbolic links' to any complex path to make it more representable
// for the object it designates:
//
//    TGeoPNEntry *pne = new TGeoPNEntry("TPC_SECTOR_2", "path_to_tpc_sect2");
//    pne->SetPhysicalNode(pn)
//
// Such a symbolic link hides the complexity of the path to the align object and 
// replaces it with a more meaningful name. In addition, TGeoPNEntry objects are
// faster to search by name and they may optionally store an additional user 
// matrix.
//
// For more details please read the misalignment section in the Users Guide.
//_____________________________________________________________________________

#include "TClass.h"
#include "TGeoManager.h"
#include "TGeoVoxelFinder.h"
#include "TGeoCache.h"
#include "TGeoMatrix.h"
#include "TGeoShape.h"
#include "TGeoVolume.h"
#include "TVirtualGeoPainter.h"

#include "TGeoPhysicalNode.h"

// statics and globals

ClassImp(TGeoPhysicalNode)

//_____________________________________________________________________________
TGeoPhysicalNode::TGeoPhysicalNode() : TNamed()
{
// Default constructor
   fLevel        = 0;
   fMatrices     = 0;
   fNodes        = 0;
   fMatrixOrig   = 0;
   SetVisibility(kTRUE);
   SetVisibleFull(kFALSE);
   SetIsVolAtt(kTRUE);
   SetAligned(kFALSE);
}

//_____________________________________________________________________________
TGeoPhysicalNode::TGeoPhysicalNode(const char *path) : TNamed(path,"")
{
// Constructor
   if (!strlen(path)) {
      Error("ctor", "path not valid");
      return;
   }
   fLevel  = 0;
   fMatrices = new TObjArray(30);
   fNodes    = new TObjArray(30);
   fMatrixOrig   = 0;
   SetPath(path);   
   SetVisibility(kTRUE);
   SetVisibleFull(kFALSE);
   SetIsVolAtt(kTRUE);
   SetAligned(kFALSE);
}

//_____________________________________________________________________________
TGeoPhysicalNode::TGeoPhysicalNode(const TGeoPhysicalNode& gpn) :
  TNamed(gpn),
  TAttLine(gpn),
  fLevel(gpn.fLevel),
  fMatrices(gpn.fMatrices),
  fNodes(gpn.fNodes),
  fMatrixOrig(gpn.fMatrixOrig)
{ 
   //copy constructor
}

//_____________________________________________________________________________
TGeoPhysicalNode& TGeoPhysicalNode::operator=(const TGeoPhysicalNode& gpn)
{
   //assignment operator
   if(this!=&gpn) {
      TNamed::operator=(gpn);
      TAttLine::operator=(gpn);
      fLevel=gpn.fLevel;
      fMatrices=gpn.fMatrices;
      fNodes=gpn.fNodes;
      fMatrixOrig=gpn.fMatrixOrig;
   } 
   return *this;
}

//_____________________________________________________________________________
TGeoPhysicalNode::~TGeoPhysicalNode()
{
// Destructor
   if (fMatrices) {
      fMatrices->Delete();
      delete fMatrices;
   }   
   if (fNodes) delete fNodes;
   if (fMatrixOrig) delete fMatrixOrig;
}

//_____________________________________________________________________________
void TGeoPhysicalNode::Align(TGeoMatrix *newmat, TGeoShape *newshape, Bool_t check, Double_t ovlp)
{
   // Align a physical node with a new relative matrix/shape.
   // Example: /TOP_1/A_1/B_1/C_1
   //    node->Align(transl_1, box) will perform:
   //    - change RELATIVE translation of C_1 node (with respect to its
   //      container volume B) to transl_1
   //    - change the shape of the C volume
   // *NOTE* The operations will affect ONLY the LAST node in the branch. All
   //   volumes/nodes in the branch represented by this physical node are
   //   CLONED so the operation does not affect other possible replicas.
   if (!newmat && !newshape) return;
   if (TGeoManager::IsLocked()) {
      Error("Align", "Not performed. Geometry in LOCKED mode !");
      return;
   }
   TGeoNode *node = GetNode();
   if (node->IsOffset()) {
      Error("Align", "Cannot align division nodes: %s\n",node->GetName());
      return;
   }   
   TGeoNode *nnode = 0;
   TGeoVolume *vm = GetVolume(0);
   TGeoVolume *vd = 0;   
   Int_t i;
   if (!IsAligned()) {
      Int_t *id = new Int_t[fLevel];
      for (i=0; i<fLevel; i++) {
         // Store daughter indexes
         vd = GetVolume(i);
         node = GetNode(i+1);
         id[i] = vd->GetIndex(node);
         if (id[i]<0) {
            Error("Align","%s cannot align node %s",GetName(), node->GetName());
            delete [] id;
            return;
         }
      }            
      for (i=0; i<fLevel; i++) {
         // Get daughter node and its id inside vm
         node = GetNode(i+1);
         // Clone daughter volume and node
         vd = node->GetVolume()->CloneVolume();
         nnode = node->MakeCopyNode();
         // Correct pointers to mother and volume
         nnode->SetVolume(vd);
         nnode->SetMotherVolume(vm);
         // Decouple old node from mother volume and connect new one
         vm->GetNodes()->RemoveAt(id[i]);
         vm->GetNodes()->AddAt(nnode,id[i]);
         fNodes->RemoveAt(i+1);
         fNodes->AddAt(nnode,i+1);
         // Consider new cloned volume as mother and continue
         vm = vd;
      }
      delete [] id;
   } else {
      nnode = GetNode();
   }         
   // Now nnode is a cloned node of the one that need to be aligned
   TGeoNodeMatrix *aligned = (TGeoNodeMatrix*)nnode;
   vm = nnode->GetMotherVolume();
   vd = nnode->GetVolume();
   if (newmat) {
      // Register matrix and make it the active one
      if (!newmat->IsRegistered()) newmat->RegisterYourself();    
      aligned->SetMatrix(newmat);
      // Update the global matrix for the aligned node
      TGeoHMatrix *global = GetMatrix();
      TGeoHMatrix *up = GetMatrix(fLevel-1);
      *global = up;
      global->Multiply(newmat);
   }
   // Change the shape for the aligned node
   if (newshape) vd->SetShape(newshape);

   // Re-compute bounding box of mother(s) if needed
   for (i=fLevel-1; i>0; i--) {
      vd = GetVolume(i);
      if (!vd->IsAssembly()) break;
      vd->GetShape()->ComputeBBox();
      if (vd->GetVoxels()) vd->GetVoxels()->SetNeedRebuild();
   }
      
   // Now we have to re-voxelize the mother volume
   TGeoVoxelFinder *voxels = vm->GetVoxels();
   if (voxels) voxels->SetNeedRebuild();
   // Eventually check for overlaps
   if (check) {
      if (voxels) {
         voxels->Voxelize();
         vm->FindOverlaps();
      }   
      // Set aligned node to be checked
      i = fLevel;
      node = GetNode(i);
      if (node->IsOverlapping()) {
         Info("Align", "The check for overlaps for node: \n%s\n cannot be performed since the node is declared possibly overlapping", 
              GetName());
      } else {        
         gGeoManager->SetCheckedNode(node);
         // Check overlaps for the first non-assembly parent node
         while ((node=GetNode(--i))) {
            if (!node->GetVolume()->IsAssembly()) break;
         }   
         if (node && node->IsOverlapping()) {
            Info("Align", "The check for overlaps for assembly node: \n%s\n cannot be performed since the parent %s is declared possibly overlapping",
                 GetName(), node->GetName());
            node = 0;
         }      
         if (node) node->CheckOverlaps(ovlp);
         gGeoManager->SetCheckedNode(0);
      }
   }      
   // Clean current matrices from cache
   gGeoManager->CdTop();
   SetAligned(kTRUE);
}   

//_____________________________________________________________________________
void TGeoPhysicalNode::cd() const
{
   gGeoManager->cd(fName.Data());
}

//_____________________________________________________________________________
void TGeoPhysicalNode::Draw(Option_t * /*option*/)
{
// Draw this node.
}

//_____________________________________________________________________________
TGeoNode *TGeoPhysicalNode::GetMother(Int_t levup) const
{
// Return parent at LEVUP generation
   Int_t ind = fLevel-levup;
   if (ind<0) return 0;
   return (TGeoNode*)fNodes->UncheckedAt(ind);
}   

//_____________________________________________________________________________
TGeoHMatrix *TGeoPhysicalNode::GetMatrix(Int_t level) const
{
// Return global matrix for node at LEVEL.
   if (level<0) return (TGeoHMatrix*)fMatrices->UncheckedAt(fLevel);
   if (level>fLevel) return 0;
   return (TGeoHMatrix*)fMatrices->UncheckedAt(level);
}

//_____________________________________________________________________________
TGeoNode *TGeoPhysicalNode::GetNode(Int_t level) const
{
// Return node in branch at LEVEL. If not specified, return last leaf.
   if (level<0) return (TGeoNode*)fNodes->UncheckedAt(fLevel);
   if (level>fLevel) return 0;
   return (TGeoNode*)fNodes->UncheckedAt(level);
}   

//_____________________________________________________________________________
TGeoVolume *TGeoPhysicalNode::GetVolume(Int_t level) const
{
// Return volume associated with node at LEVEL in the branch
   TGeoNode *node = GetNode(level);
   if (node) return node->GetVolume();
   return 0;
}

//_____________________________________________________________________________
TGeoShape *TGeoPhysicalNode::GetShape(Int_t level) const
{
// Return shape associated with volume.
   TGeoVolume *vol = GetVolume(level);
   if (vol) return vol->GetShape();
   return 0;
}   

//_____________________________________________________________________________
void TGeoPhysicalNode::Paint(Option_t * /*option*/)
{
// Paint this node and its content according to visualization settings.
   TVirtualGeoPainter *painter = gGeoManager->GetGeomPainter();
   if (!painter) return;
//   painter->PaintNode(this, option);
}

//_____________________________________________________________________________
void TGeoPhysicalNode::Print(Option_t * /*option*/) const
{
// Print info about this node.
   printf("TGeoPhysicalNode: %s level=%d aligned=%d\n", fName.Data(), fLevel, IsAligned());
   for (Int_t i=0; i<=fLevel; i++) {
      printf(" level %d: node %s\n", i, GetNode(i)->GetName());
      printf(" local matrix:\n");
      if (GetNode(i)->GetMatrix()->IsIdentity()) printf("   IDENTITY\n");
      else GetNode(i)->GetMatrix()->Print();
      printf(" global matrix:\n");
      if (GetMatrix(i)->IsIdentity()) printf("   IDENTITY\n");
      else GetMatrix(i)->Print();
   }   
   if (IsAligned() && fMatrixOrig) {
      printf(" original local matrix:\n");
      fMatrixOrig->Print();
   }
}      

//_____________________________________________________________________________
void TGeoPhysicalNode::Refresh()
{
// Refresh this physical node. Called for all registered physical nodes
// after an Align() call.
   SetPath(fName.Data());
}   

//_____________________________________________________________________________
void TGeoPhysicalNode::SetBranchAsState()
{
// Set node branch according to current state
   TGeoNodeCache *cache = gGeoManager->GetCache();
   if (!cache) {
      Error("SetBranchAsState","no state available");
      return;
   }
   if (!cache->IsDummy()) {
      Error("SetBranchAsState", "not implemented for full cache");
      return;
   }      
   if (!fNodes)    fNodes = new TObjArray(30);
   if (!fMatrices) fMatrices = new TObjArray(30);
   TGeoHMatrix **matrices = (TGeoHMatrix **) cache->GetMatrices();
   TGeoNode **branch = (TGeoNode **) cache->GetBranch();

   Bool_t refresh = (fLevel>0)?kTRUE:kFALSE;
   if (refresh) {
      TGeoHMatrix *current;
      for (Int_t i=0; i<=fLevel; i++) {
         fNodes->AddAtAndExpand(branch[i],i);
         current = (TGeoHMatrix*)fMatrices->UncheckedAt(i);
         *current = *matrices[i];
      }
      return;
   }
   fLevel = gGeoManager->GetLevel();   
   for (Int_t i=0; i<=fLevel; i++) {
      fNodes->AddAtAndExpand(branch[i],i);
      fMatrices->AddAtAndExpand(new TGeoHMatrix(*matrices[i]),i);
   }   
   TGeoNode *node = (TGeoNode*)fNodes->UncheckedAt(fLevel);
   if (!fMatrixOrig) fMatrixOrig = new TGeoHMatrix();
   *fMatrixOrig = node->GetMatrix();
}

//_____________________________________________________________________________
void TGeoPhysicalNode::SetMatrixOrig(const TGeoMatrix *local)
{
// Allows PN entries (or users) to preset the local original matrix for the
// last node pointed by the path.
   if (!fMatrixOrig) fMatrixOrig = new TGeoHMatrix();
   if (!local) fMatrixOrig->Clear();
   *fMatrixOrig = local;
}   

//_____________________________________________________________________________
Bool_t TGeoPhysicalNode::SetPath(const char *path)
{
// Specify the path for this node.
   if (!gGeoManager->cd(path)) {
      Error("SetPath","wrong path -> maybe RestoreMasterVolume");
      return kFALSE;
   }
   SetBranchAsState();
   return kTRUE;
}

ClassImp(TGeoPNEntry)

//_____________________________________________________________________________
TGeoPNEntry::TGeoPNEntry()
{
// Default constructor
   fNode = 0;
   fMatrix = 0;
   fGlobalOrig = 0;
}

//_____________________________________________________________________________
TGeoPNEntry::TGeoPNEntry(const char *name, const char *path)
            :TNamed(name, path)
{
// Default constructor
   if (!gGeoManager || !gGeoManager->IsClosed() || !gGeoManager->CheckPath(path)) {
      TString errmsg("Cannot define a physical node link without a closed geometry and a valid path !");
      Error("ctor", errmsg.Data());
      throw errmsg;
      return;
   }   
   gGeoManager->PushPath();
   gGeoManager->cd(path);
   fGlobalOrig = new TGeoHMatrix();
   *fGlobalOrig = gGeoManager->GetCurrentMatrix();
   gGeoManager->PopPath();
   fNode = 0;
   fMatrix = 0;
}

//_____________________________________________________________________________
TGeoPNEntry::~TGeoPNEntry()
{
// Destructor
   if (fMatrix && !fMatrix->IsRegistered()) delete fMatrix;
   delete fGlobalOrig;
}
   
//_____________________________________________________________________________
void TGeoPNEntry::SetPhysicalNode(TGeoPhysicalNode *node)
{
// Setter for the corresponding physical node.
   if (fNode && node) {
      Warning("SetPhysicalNode", "Physical node changed for entry %s", GetName());
      Warning("SetPhysicalNode", "=== New path: %s", node->GetName());
   }
   fNode = node;   
}
   
//_____________________________________________________________________________
void TGeoPNEntry::SetMatrix(const TGeoHMatrix *mat)
{
// Set the additional matrix for this node entry. The matrix will be deleted
// by this class unless registered by the user to gGeoManager
   fMatrix = mat;
}